37 It happened on the next day, when they had come down from the mountain, that a great multitude met him. 38 Behold, a man from the crowd called out, saying, “Teacher, I beg you to look at my son, for he is my only child. 39 Behold, a spirit takes him, he suddenly cries out, and it convulses him so that he foams, and it hardly departs from him, bruising him severely. 40 I begged your disciples to cast it out, and they couldn’t.” 41 Jesus answered, “Faithless and perverse generation, how long shall I be with you and bear with you? Bring your son here.” 42 While he was still coming, the demon threw him down and convulsed him violently. But Jesus rebuked the unclean spirit, and healed the boy, and gave him back to his father.
43 They were all astonished at the majesty of God.
But while all were marveling at all the things which Jesus did, he said to his disciples,
44 “Let these words sink into your ears, for the Son of Man will be delivered up into the hands of men.” 45 But they didn’t understand this saying. It was concealed from them, that they should not perceive it, and they were afraid to ask him about this saying.
Matthew Henry's Commentary on Luke 9:37-45
Commentary on Luke 9:37-42
(Read Luke 9:37-42)
How deplorable the case of this child! He was under the power of an evil spirit. Disease of that nature are more frightful than such as arise merely from natural causes. What mischief Satan does where he gets possession! But happy those that have access to Christ! He can do that for us which his disciples cannot. A word from Christ healed the child; and when our children recover from sickness, it is comfortable to receive them as healed by the hand of Christ.
Commentary on Luke 9:43-50
(Read Luke 9:43-50)
This prediction of Christ's sufferings was plain enough, but the disciples would not understand it, because it agreed not with their notions. A little child is the emblem by which Christ teaches us simplicity and humility. What greater honour can any man attain to in this world, than to be received by men as a messenger of God and Christ; and to have God and Christ own themselves received and welcomed in him! If ever any society of Christians in this world, had reason to silence those not of their own communion, the twelve disciples at this time had; yet Christ warned them not to do the like again. Those may be found faithful followers of Christ, and may be accepted of him, who do not follow with us.